PRIOR CONCURRENT THERAPY: Biologic therapy: At least 4 weeks since prior biologic therapy and recovered No more than 1 prior biologic regimen No other concurrent biologic therapy Chemotherapy: At least 4 weeks since prior cytotoxic therapy and recovered No more than 1 prior cytotoxic regimen No concurrent cytotoxic therapy Endocrine therapy: At least 4 weeks since prior hormonal therapy and recovered No more than 1 prior hormonal regimen No concurrent hormonal therapy Radiotherapy: At least 4 weeks since prior radiotherapy No concurrent radiotherapy Surgery: At least 4 weeks since prior major surgery